1. Field of the Invention
The present invention relates to a power saving circuit, and more particularly, to a power saving circuit for a PWM circuit.
2. Description of Related Art
With the progress of modern science, the functionality of the electronic devices becomes better and better for people it is more the convenience in the living. Nowadays, greater part of the electronic devices includes a Pulse Width Modulation (PWM) circuit to generate a PWM signal. The PWM signal serves a switching signal for controlling other circuits of the electronic device, such as power supply, power converter, regulator, and driving circuit, etc. The switching signal of the PWM circuit is disabled to control the controlled circuits of the electronic device. At this moment in time, the actions of a part of the internal circuits of the PWM circuit or a part of the internal circuits of the electronic device are not effective, such as protection circuit of the PWM circuit. The protection circuit is utilized to control the PWM circuit in response to the state of the controlled circuits of the electronic device. The action of the protection circuit is not effective due to the controlled circuits of the electronic device is disabled by the switching signal. However, these no effect internal circuits are still operating and consuming power that wastes the power.